U.S. patent application number 16/374558 was filed with the patent office on 2019-10-10 for goa circuit and driving method thereof, and touch display apparatus.
The applicant listed for this patent is BOE TECHNOLOGY GROUP CO., LTD., Chongqing BOE Optoelectronics Technology Co., Ltd.. Invention is credited to Shuai CHEN, Xing DONG, Shuang HU, Xuebo LIANG, Xiuzhu TANG, Zhenguo TIAN, Lijun XIONG.
Application Number | 20190311690 16/374558 |
Document ID | / |
Family ID | 63199595 |
Filed Date | 2019-10-10 |
![](/patent/app/20190311690/US20190311690A1-20191010-D00000.png)
![](/patent/app/20190311690/US20190311690A1-20191010-D00001.png)
![](/patent/app/20190311690/US20190311690A1-20191010-D00002.png)
![](/patent/app/20190311690/US20190311690A1-20191010-D00003.png)
![](/patent/app/20190311690/US20190311690A1-20191010-D00004.png)
![](/patent/app/20190311690/US20190311690A1-20191010-D00005.png)
![](/patent/app/20190311690/US20190311690A1-20191010-D00006.png)
![](/patent/app/20190311690/US20190311690A1-20191010-D00007.png)
United States Patent
Application |
20190311690 |
Kind Code |
A1 |
CHEN; Shuai ; et
al. |
October 10, 2019 |
GOA CIRCUIT AND DRIVING METHOD THEREOF, AND TOUCH DISPLAY
APPARATUS
Abstract
A GOA circuit includes a plurality of GOA units. First input
terminals of a first-level GOA unit to a (N/2)th-level GOA unit are
coupled to a first signal terminal, and a first input terminal of
any one of other GOA units is coupled to an output terminal of a
(N/2)th-level GOA unit located in front of the any one of other GOA
units. Second input terminals of a last-level GOA unit to a (N/2)th
last-level GOA unit are coupled to a second signal terminal, and a
second input terminal of any one of other GOA units is coupled to
an output terminal of a (N/2)th-level GOA unit located behind the
any one of other GOA units. N is the number of clock signals in one
clock period. N/2 cascaded GOA units of the GOA circuit are
included in a pull-up node potential holding unit, and output
terminals of the N/2 cascaded GOA units are not coupled to gate
lines.
Inventors: |
CHEN; Shuai; (Beijing,
CN) ; DONG; Xing; (Beijing, CN) ; TIAN;
Zhenguo; (Beijing, CN) ; LIANG; Xuebo;
(Beijing, CN) ; XIONG; Lijun; (Beijing, CN)
; TANG; Xiuzhu; (Beijing, CN) ; HU; Shuang;
(Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Chongqing BOE Optoelectronics Technology Co., Ltd.
BOE TECHNOLOGY GROUP CO., LTD. |
Chongqing
Beijing |
|
CN
CN |
|
|
Family ID: |
63199595 |
Appl. No.: |
16/374558 |
Filed: |
April 3, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G09G 2300/0426 20130101;
G09G 2310/08 20130101; G06F 3/0416 20130101; G09G 2300/0408
20130101; G09G 2310/0286 20130101; G09G 3/3677 20130101; G06F
3/0412 20130101 |
International
Class: |
G09G 3/36 20060101
G09G003/36; G06F 3/041 20060101 G06F003/041 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 10, 2018 |
CN |
201810316406.9 |
Claims
1. A GOA circuit, comprising a plurality of cascaded GOA units,
wherein each GOA unit includes a first input terminal, a second
input terminal, an output terminal, voltage terminals and a clock
signal terminal; and the GOA circuit is configured to receive N
clock signals in one clock period, the clock signal terminal of the
GOA unit is configured to receive one of the N clock signals in one
clock period, and N is a positive even number; first input
terminals of a first-level GOA unit to a (N/2)th-level GOA unit are
coupled to a first signal terminal, a first input terminal of a
(N/2+1)th-level GOA unit is coupled to an output terminal of the
first-level GOA unit, a first input terminal of a (N/2+2)th-level
GOA unit is coupled to an output terminal of a second-level GOA
unit, and so on; second input terminals of a last-level GOA unit to
a (N/2)th last-level GOA unit are coupled to a second signal
terminal, a second input terminal of a (N/2+1)th last-level GOA
unit is coupled to an output terminal of the last-level GOA unit, a
second input terminal of a (N/2+2)th last-level GOA unit is coupled
to an output terminal of a second last-level GOA unit, and so on;
and N/2 cascaded GOA units of the plurality of cascaded GOA units
are included in a pull-up node potential holding unit, and output
terminals of the GOA units in the pull-up node potential holding
unit are not coupled to gate lines.
2. The GOA circuit according to claim 1, wherein the GOA unit
further includes a first input sub-circuit, a second input
sub-circuit, an output sub-circuit, a pull-down control sub-circuit
and a pull-down sub-circuit; the first input sub-circuit is coupled
to the first input terminal and a pull-up node, and the first input
sub-circuit is configured to input a signal from the first input
terminal to the pull-up node under control of the first input
terminal; the second input sub-circuit is coupled to the second
input terminal, the pull-up node and a first voltage terminal, and
the second input sub-circuit is configured to output a signal from
the first voltage terminal to the pull-up node under control of the
second input terminal; the output sub-circuit is coupled to the
pull-up node, the clock signal terminal and the output terminal,
and the output sub-circuit is configured to output a signal from
the clock signal terminal to the output terminal under control of a
potential at the pull-up node; the pull-down control sub-circuit is
coupled to a second voltage terminal, the pull-up node, a pull-down
node and the first voltage terminal, the pull-down control
sub-circuit is configured to output the signal from the first
voltage terminal to the pull-down node under control of a potential
at the pull-up node, and output a voltage from the second voltage
terminal to the pull-down node under control of the second voltage
terminal; and the pull-down sub-circuit is coupled to the pull-down
node, the pull-up node, the output terminal and the first voltage
terminal, and the pull-down sub-circuit is configured to output the
signal from the first voltage terminal to the the output terminal
and the pull-up node under control of a potential at the pull-down
node.
3. The GOA circuit according to claim 2, wherein each of
(N/2)-level GOA units disposed behind the pull-up node potential
holding unit further includes a denoising sub-circuits, the
denoising sub-circuit of any GOA unit of the (N/2)-level GOA units
located behind the pull-up node potential holding unit is coupled
to the first voltage terminal, an output terminal of the same-level
GOA unit and an output terminal of a corresponding-level GOA unit
in the pull-up node potential holding unit, and the denoising
sub-circuit is configured to denoise an output signal of the output
terminal of the same-level GOA unit under control of the output
signal from the output terminal of the corresponding-level GOA unit
in the pull-up node potential holding unit in a touch scan
period.
4. The GOA circuit according to claim 2, wherein the first input
sub-circuit includes a first transistor, a gate and a first
electrode of the first transistor is coupled to the first input
terminal, and a second electrode of the first transistor is coupled
to the pull-up node.
5. The GOA circuit according to claim 2, wherein the second input
sub-circuit includes a second transistor, a gate of the second
transistor is coupled to the second input terminal, a first
electrode of the second transistor is coupled to the pull-up node,
and a second electrode of the second transistor is coupled to the
first voltage terminal.
6. The GOA circuit according to claim 2, wherein the output
sub-circuit includes a third transistor and a first capacitor; a
gate of the third transistor is coupled to the pull-up node, a
first electrode of the third transistor is coupled to the clock
signal terminal, and a second electrode of the third transistor is
coupled to the output terminal; and one end of the first capacitor
is coupled to the pull-up node, and another end of the first
capacitor is coupled to the output terminal.
7. The GOA circuit according to claim 2, wherein the pull-down
control sub-circuit includes a fourth transistor, a fifth
transistor, a sixth transistor and a seventh transistor; a gate and
a first electrode of the fourth transistor are coupled to the
second voltage terminal, and a second electrode of the fourth
transistor is coupled to a gate of the fifth transistor and a first
electrode of the seventh transistor; and a first electrode of the
fifth transistor is coupled to the second voltage terminal, and a
second electrode of the fifth transistor is coupled to the
pull-down node; and a gate of the sixth transistor is coupled to
the pull-up node, a first electrode of the sixth transistor is
coupled to the pull-down node, and a second electrode of the sixth
transistor is coupled to the first voltage terminal; and a gate of
the seventh transistor is coupled to the pull-up node, and a second
electrode of the seventh transistor is coupled to the first voltage
terminal.
8. The GOA circuit according to claim 2, wherein the pull-down
sub-circuit includes an eighth transistor and a ninth transistor; a
gate of the eighth transistor is coupled to the pull-down node, a
first electrode of the eighth transistor is coupled to the pull-up
node, and a second electrode of the eighth transistor is coupled to
the first voltage terminal; and a gate of the ninth transistor is
coupled to the pull-down node, a first electrode of the ninth
transistor is coupled to the output terminal, and a second
electrode of the nine transistor is coupled to the first voltage
terminal.
9. The GOA circuit according to claim 3, wherein the denoising
sub-circuit includes a tenth transistor, a gate of the tenth
transistor is coupled to the output terminal of the
corresponding-level GOA unit in the pull-up node potential holding
unit, a first electrode of the tenth transistor is coupled to the
output terminal of the same-level GOA unit, and a second electrode
of the tenth transistor is coupled to the first voltage
terminal.
10. The GOA circuit according to claim 4, wherein the transistor is
a N-type transistor or a P-type transistor.
11. A method of driving the GOA circuit according to claim 1, the
method comprising: in a touch scan period, providing low level
clock signals to (N/2)-level GOA units located behind the pull-up
node potential holding unit, so that gate line scan signals are not
output from the (N/2)-level GOA units located behind the pull-up
node potential holding unit in the touch scan period; and in the
touch scan period, providing a high level clock signal to each GOA
unit in the pull-up node potential holding unit, so that a high
level signal is output from an output terminal of each GOA unit in
the pull-up node potential holding unit, thereby causing that
pull-up nodes of the (N/2)-level GOA units located behind the
pull-up node potential holding unit are maintained at a high level
in the touch scan period.
12. The method of driving the GOA circuit according to claim 11,
wherein each of the (N/2)-level GOA units located behind the
pull-up node potential holding unit includes a denoising
sub-circuit, and the method further includes: in the touch scan
period, controlling the denoising sub-circuit by using a high level
signal output from an output terminal of a corresponding GOA unit
in the pull-up node potential holding unit, so that the denoising
sub-circuit denoises an output signal from a corresponding one of
the (N/2)-level GOA units located behind the pull-up node potential
holding unit.
13. The method of driving the GOA circuit according to claim 11,
wherein the method further includes: in an input period, inputting,
by a first input sub-circuit, a signal from the first input
terminal to a pull-up node under control of the first input
terminal; in an output period, outputting, by an output
sub-circuit, a signal from the clock signal terminal as a gate line
scan signal to the output terminal under control of a potential at
the pull-up node; and in a reset period, pulling down, by a second
input sub-circuit, the potential at the pull-up node to a potential
at a first voltage terminal under control of the second input
terminal, outputting, by a pull-down control sub-circuit, a signal
from a second voltage terminal to a pull-down node under control of
the second voltage terminal, and pulling down, by a pull-down
sub-circuit, potentials at the output terminal and the pull-up node
to the potential at the first voltage terminal under control of a
potential at the pull-down node, wherein the input period, the
output period and the reset period are included in a display
period.
14. A touch display apparatus, comprising the GOA circuit according
to claim 1.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to Chinese Patent
Application No. 201810316406.9, filed with the Chinese Patent
Office on Apr. 10, 2018, titled "GOA CIRCUIT AND DRIVING METHOD
THEREOF, AND TOUCH DISPLAY APPARATUS", which is incorporated herein
by reference in its entirety.
TECHNICAL FIELD
[0002] The present disclosure relates to the field of display
technologies, and in particular, to a GOA circuit and a driving
method thereof, and a touch display apparatus.
BACKGROUND
[0003] In order to pursue a lower cost and a narrower bezel of a
liquid crystal display (LCD), a gate driver on array (GOA)
technology, in which thin film transistors (TFTs) each driven by a
corresponding gate are directly fabricated on a base substrate of
an array substrate, is increasingly used in LCD products, thereby
eliminating a space occupation of an integrated circuit (IC)
bonding area and a fan-out area, and reducing the cost in materials
and manufacturing processes etc., and narrowing the frames on both
sides of gate lines of a panel.
SUMMARY
[0004] In a first aspect, a GOA circuit is provided. The GOA
circuit includes a plurality of cascaded GOA units, and each GOA
unit includes a first input terminal, a second input terminal, an
output terminal, voltage terminals and a clock signal terminal. The
GOA circuit is configured to receive N clock signals in one clock
period, and the clock signal terminal of the GOA unit is configured
to receive one of the N clock signals in one clock period, and N is
a positive even number. First input terminals of a first-level GOA
unit to a (N/2)th-level GOA unit are coupled to a first signal
terminal, a first input terminal of a (N/2+1)th-level GOA unit is
coupled to an output terminal of the first-level GOA unit, a first
input terminal of a (N/2+2)th-level GOA unit is coupled to an
output terminal of a second-level GOA unit, and so on. Second input
terminals of a last-level GOA unit to a (N/2)th last-level GOA unit
are coupled to a second signal terminal, a second input terminal of
a (N/2+1)th last-level GOA unit is coupled to an output terminal of
the last-level GOA unit, a second input terminal of a (N/2+2)th
last-level GOA unit is coupled to an output terminal of a second
last-level GOA unit, and so on. N/2 cascaded GOA units of the
plurality of cascaded GOA units are included in a pull-up node
potential holding unit, and output terminals of the GOA units in
the pull-up node potential holding unit are not coupled to gate
lines.
[0005] In some embodiments, the GOA unit further includes a first
input sub-circuit, a second input sub-circuit, an output
sub-circuit, a pull-down control sub-circuit and a pull-down
sub-circuit. The first input sub-circuit is coupled to the first
input terminal and a pull-up node, and the first input sub-circuit
is configured to input a signal from the first input terminal to
the pull-up node under control of the first input terminal. The
second input sub-circuit is coupled to the second input terminal,
the pull-up node and a first voltage terminal, and the second input
sub-circuit is configured to output a signal from the first voltage
terminal to the pull-up node under control of the second input
terminal. The output sub-circuit is coupled to the pull-up node,
the clock signal terminal and the output terminal, and the output
sub-circuit is configured to output a signal from the clock signal
terminal to the output terminal under control of a potential at the
pull-up node. The pull-down control sub-circuit is coupled to a
second voltage terminal, the pull-up node, a pull-down node and the
first voltage terminal, and the pull-down control sub-circuit is
configured to output the signal from the first voltage terminal to
the pull-down node under control of a potential at the pull-up
node, and output a voltage from the second voltage terminal to the
pull-down node under control of the second voltage terminal. The
pull-down sub-circuit is coupled to the pull-down node, the pull-up
node, the output terminal and the first voltage terminal, and the
pull-down sub-circuit is configured to output the signal from the
first voltage terminal to the the output terminal and the pull-up
node under control of a potential at the pull-down node.
[0006] In some embodiments, each of (N/2)-level GOA units disposed
behind the pull-up node potential holding unit further includes a
denoising sub-circuit. The denoising sub-circuit of any GOA unit of
the (N/2)-level GOA units located behind the pull-up node potential
holding unit is coupled to the first voltage terminal, an output
terminal of the same-level GOA unit and an output terminal of a
corresponding-level GOA unit in the pull-up node potential holding
unit. The denoising sub-circuit is configured to denoise an output
signal of the output terminal of the same-level GOA unit under
control of the output signal from the output terminal of the
corresponding-level GOA unit in the pull-up node potential holding
unit in a touch scan period.
[0007] In some embodiments, the first input sub-circuit includes a
first transistor, a gate and a first electrode of the first
transistor is coupled to the first input terminal, and a second
electrode of the first transistor is coupled to the pull-up
node.
[0008] In some embodiments, the second input sub-circuit includes a
second transistor, a gate of the second transistor is coupled to
the second input terminal, a first electrode of the second
transistor is coupled to the pull-up node, and a second electrode
of the second transistor is coupled to the first voltage
terminal.
[0009] In some embodiments, the output sub-circuit includes a third
transistor and a first capacitor. A gate of the third transistor is
coupled to the pull-up node, a first electrode of the third
transistor is coupled to the clock signal terminal, and a second
electrode of the third transistor is coupled to the output
terminal. One end of the first capacitor is coupled to the pull-up
node, and another end of the first capacitor is coupled to the
output terminal.
[0010] In some embodiments, the pull-down control sub-circuit
includes a fourth transistor, a fifth transistor, a sixth
transistor and a seventh transistor. A gate and a first electrode
of the fourth transistor are coupled to the second voltage
terminal, and a second electrode of the fourth transistor is
coupled to a gate of the fifth transistor and a first electrode of
the seventh transistor. A first electrode of the fifth transistor
is coupled to the second voltage terminal, and a second electrode
of the fifth transistor is coupled to the pull-down node. A gate of
the sixth transistor is coupled to the pull-up node, a first
electrode of the sixth transistor is coupled to the pull-down node,
and a second electrode of the sixth transistor is coupled to the
first voltage terminal. A gate of the seventh transistor is coupled
to the pull-up node, and a second electrode of the seventh
transistor is coupled to the first voltage terminal.
[0011] In some embodiments, the pull-down sub-circuit includes an
eighth transistor and a ninth transistor. A gate of the eighth
transistor is coupled to the pull-down node, a first electrode of
the eighth transistor is coupled to the pull-up node, and a second
electrode of the eighth transistor is coupled to the first voltage
terminal. A gate of the ninth transistor is coupled to the
pull-down node, a first electrode of the ninth transistor is
coupled to the output terminal, and a second electrode of the nine
transistor is coupled to the first voltage terminal.
[0012] In some embodiments, the denoising sub-circuit includes a
tenth transistor. A gate of the tenth transistor is coupled to the
output terminal of the corresponding-level GOA unit in the pull-up
node potential holding unit, a first electrode of the tenth
transistor is coupled to the output terminal of the same-level GOA
unit, and a second electrode of the tenth transistor is coupled to
the first voltage terminal.
[0013] In some embodiments, the transistor is a N-type transistor
or a P-type transistor.
[0014] In a second aspect, a method of driving the GOA circuit
according to the first aspect is provided. The driving method
includes: in a touch scan period, providing low level clock signals
to (N/2)-level GOA units located behind the pull-up node potential
holding unit, so that gate line scan signals are not output from
the (N/2)-level GOA units located behind the pull-up node potential
holding unit in the touch scan period; and providing a high level
clock signal to each GOA unit in the pull-up node potential holding
unit, so that a high level signal is output from an output terminal
of each GOA unit in the pull-up node potential holding unit,
thereby causing that pull-up nodes of the (N/2)-level GOA units
located behind the pull-up node potential holding unit are
maintained at a high level in the touch scan period.
[0015] In some embodiments, each of the (N/2)-level GOA units
located behind the pull-up node potential holding unit includes a
denoising sub-circuit, and the method further includes: in the
touch scan period, controlling the denoising sub-circuit by using a
high level signal output from an output terminal of a corresponding
GOA unit in the pull-up node potential holding unit, so that the
denoising sub-circuit denoises an output signal from a
corresponding one of the (N/2)-level GOA units located behind the
pull-up node potential holding unit.
[0016] In some embodiments, the method of driving the GOA circuit
further includes: in an input period, inputting, by a first input
sub-circuit, a signal from the first input terminal to a pull-up
node under control of the first input terminal; in an output
period, outputting, by an output sub-circuit, a signal from the
clock signal terminal as a gate line scan signal to the output
terminal under control of a potential at the pull-up node; and in a
reset period, pulling down, by a second input sub-circuit, a
potential at the pull-up node to a potential at a first voltage
terminal under control of the second input terminal, outputting, by
a pull-down control sub-circuit, a signal from the second voltage
terminal to a pull-down node under control of the second voltage
terminal, and pulling down, by a pull-down sub-circuit, potentials
at the output terminal and the pull-up node to the potential at the
first voltage terminal under control of a potential at the
pull-down node. The input period, the output period and the reset
period are included in a display period.
[0017] In a third aspect, a touch display apparatus is provided.
The touch display apparatus includes the GOA circuit according to
the first aspect.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to describe technical solutions in embodiments of
the present disclosure more clearly, the accompanying drawings to
be used in the description of disclosure will be introduced
briefly. Obviously, the accompanying drawings to be described below
are merely some embodiments of the present disclosure, and a person
of ordinary skill in the art can obtain other drawings according to
these drawings without paying any creative effort.
[0019] FIG. 1 is a schematic circuit diagram of a GOA unit used in
a touch display screen;
[0020] FIG. 2 shows a timing diagram of controlling a GOA circuit
formed by cascading GOA units shown in FIG. 1;
[0021] FIG. 3 is a schematic structural diagram of a GOA circuit
formed by cascading GOA units shown in FIG. 1;
[0022] FIG. 4 is a schematic structural diagram of a GOA circuit
according to some embodiments of the present disclosure;
[0023] FIG. 5 is a schematic structural diagram of one of GOA units
in the GOA circuit shown in FIG. 4 according to some embodiments of
the present disclosure;
[0024] FIG. 6 is a schematic circuit diagram of GOA units shown in
FIG. 5 according to some embodiments of the present disclosure;
[0025] FIG. 7 shows a timing diagram of controlling the GOA circuit
shown in FIG. 4 according to the embodiments of the present
disclosure; and
[0026] FIG. 8 shows a touch display device having the built-in GOA
circuit shown in FIG. 4 according to some embodiments of the
present disclosure.
DETAILED DESCRIPTION
[0027] The technical solutions in the embodiments of the present
disclosure will be described clearly and completely below with
reference to the accompanying drawings in the embodiments of the
present disclosure. Obviously, the described embodiments are merely
some but not all of embodiments of the present disclosure. All
other embodiments made on the basis of the embodiments of the
present disclosure by a person of ordinary skill in the art without
paying any creative effort shall be included in the protection
scope of the present disclosure.
[0028] A touch screen generally uses an in cell touch technology to
integrate touch elements into the liquid crystal display, so that
the liquid crystal display does not need to be assembled with a
touch panel to achieve a touch effect.
[0029] With a size of a touch screen gradually increasing,
requirements for a touch report rate are also higher. The touch
report rate is the number of times that contact information of the
touch screen is reported to a host every second. Currently, a touch
report method is to insert a touch scan signal between two display
frames. That is, a touch scan period is inserted in a blanking
period between two adjacent display frames (that is, a time period
after an end of one image frame and before a start of a next image
frame). This method is also referred to as a long horizon blanking
(LHB) mode. The touch report rate of this mode is the same as a
display frame rate, both of which are 60 Hz/s.
[0030] However, it will be noted that due to an existence of a
touch scan period, in first few GOA units after the touch scan
period, voltages on the pull-up nodes PU of the few GOA units may
be attenuated due to the electric leakage of TFTs during the touch
scan, thereby causing that gate turn-on signals output from the
output terminals of the few GOA units, i.e., the gate turn-on
signals output from the output terminals of the few GOA units that
are different from other GOA units, are attenuated after the touch
scan period, and causing that a horizontal line (H-line) phenomenon
occurs at fixed positions in the pixel area, and resulting in a
poor display.
[0031] As shown in FIG. 1, a GOA unit used in a touch display
screen includes ten transistors and one capacitor, which may be
referred to as a 10T1C GOA unit. FIG. 3 is a schematic diagram of a
GOA circuit formed by cascading a plurality of GOA units shown in
FIG. 1. The GOA circuit uses 4 clock signals (i.e., CLK1, CLK2,
CLK3, and CLK4), and the GOA circuit is applied into a touch
display screen of the LHB mode. FIG. 2 shows a timing diagram of
controlling the GOA circuit shown in FIG. 3.
[0032] As shown in FIGS. 2 and 3, a touch scan process is performed
on a (N+1)th-level GOA unit and a (N+2)th-level GOA unit during the
touch scan period. In the touch scan period, the clock signals
CLK1, CLK2, CLK3, and CLK4 are all at a low level, and pull-up
nodes PU of a Nth-level GOA unit, the (N+1)th-level GOA unit, the
(N+2)th-level GOA unit and a (N+3)th-level GOA unit are always
maintained at a high level. As shown in FIG. 2, due to the
existence of the touch scan period, the voltages on the pull-up
nodes PU of adjacent four GOA units, i.e., the Nth-level GOA unit,
the (N+1)th-level GOA unit, the (N+2)th-level GOA unit and the
(N+3)th-level GOA unit, may be attenuated due to the electric
leakage of the TFTs in the four GOA units. After the end of the
touch scan period, the gate line scan signals are output from the
(N+2)th-level GOA unit and the (N+3)th-level GOA unit in sequence.
However, since the voltages on the pull-up nodes PU of the
(N+2)th-level GOA unit and the (N+3)th-level GOA unit are lower
than the voltage required to normally turn on a gate of the
transistor M3 shown in FIG. 1, the voltages of the gate line scan
signals output from the (N+2)th-level GOA unit and the
(N+3)th-level GOA unit are also low, thereby causing that the TFTs
connected to corresponding gate lines are not fully turned on and
that the H-line phenomenon occurs at the fixed positions.
[0033] The GOA unit shown in FIG. 1 uses a gate control high (GCH)
signal as a denoising circuit control source (a DC denoising mode).
As shown in FIG. 1, when the GCH signal is at a high level, a
transistor M9 is turned on, and the high level of the GCH signal is
transmitted to a gate of a transistor M5 under control of the GCH
signal. In this case, the transistor M5 is turned on, which causes
that the high level of the GCH signal is output to the pull-down
node PD under the control of the GCH signal. Since the pull-down
node PD is coupled to a gate of a transistor M11, the transistor
M11 is turned on, and a potential at the output terminal of the GOA
unit is pulled down by the transistor M11 to a potential at the
voltage terminal VSS, thereby denoising the output signal of the
GOA unit. However, as shown in FIGS. 1 and 2, in the touch scan
period, the pull-up nodes PU of the Nth-level GOA unit, the
(N+1)th-level GOA unit, the (N+2)th-level GOA unit and the
(N+3)th-level GOA unit are at a high level. In this case, a
transistor M6 is turned on, the potential at the pull-down node PD
is pulled down by the transistor M6 to the potential at the voltage
terminal VSS, and the pull-down node PD is at a low level. In this
case, the transistor M3 is turned on and the clock signal is
transmitted to the output terminal OUT of the GOA unit, and the
transistor M11 for denoising the output signal of the GOA unit is
not turned on. When a touch signal is coupled to the clock signal,
the Nth-level GOA unit, the (N+1)th-level GOA unit, the
(N+2)th-level GOA unit and the (N+3)th-level GOA unit may output
signals with noise.
[0034] In order to avoid the above problem, as shown in FIGS. 1 and
3, a gate control low (GCL) signal and a transistor M4 are
introduced into the GOA circuit, and the GCL signal is at a high
level in the touch scan period, which causes the transistor M4 to
be turned on to denoise the output signal of the GOA unit described
above in this period.
[0035] In summary, due to the existence of the touch scan period,
the electric leakage of the pull-up nodes of several GOA units
required to be turned on in the touch display screen occurs, which
causes that the H-line phenomenon occurs at the fixed positions due
to insufficient output voltages from the several GOA units after
the end of the touch scan period. Moreover, since the GCL signal is
introduced, a wire width of a pulse generator (PLG) and the number
of transistors are increased, and thereby a power consumption of
the GOA circuit is increased.
[0036] Based on this, some embodiments of the present disclosure
provide a GOA circuit. As shown in FIG. 4, the GOA circuit includes
a plurality of cascaded GOA units, and each GOA unit includes a
first input terminal INPUT1, a second input terminal INPUT2, an
output terminal OUT, voltage terminals (including a first voltage
terminal VSS and a second voltage terminal GCH) and a clock signal
terminal CLK.
[0037] The GOA circuit is configured to receive N clock signals in
one clock period, and the clock signal terminal CLK of each GOA
unit is configured to receive one of the N clock signals in one
clock period. N is a positive even number.
[0038] First input terminals INPUT1 of a first-level GOA unit to a
(N/2)th-level GOA unit are coupled to a first signal terminal, a
first input terminal INPUT1 of a (N/2+1)th-level GOA unit is
coupled to an output terminal OUT of the first-level GOA unit, a
first input terminal INPUT1 of a (N/2+2)th-level GOA unit is
coupled to an output terminal OUT of a second-level GOA unit, and
so on.
[0039] Second input terminals INPUT2 of a last-level GOA unit to a
(N/2)th last-level GOA unit are coupled to a second signal
terminal, a second input terminal INPUT2 of a (N/2+1)th last-level
GOA unit is coupled to an output terminal OUT of the last-level GOA
unit, a second input terminal INPUT2 of a (N/2+2)th last-level GOA
unit is coupled to an output terminal OUT of a second last-level
GOA unit, and so on.
[0040] In some embodiments, as shown in FIG. 4, N/2 cascaded GOA
units of the plurality of cascaded GOA units are included in a
pull-up node potential holding unit 10, and output terminals of the
GOA units in the pull-up node potential holding unit 10 are not
coupled to gate lines, that is, these GOA units do not output gate
line scan signals.
[0041] In some embodiments, as shown in FIG. 4, N is equal to 4,
that is, the number of the clock signals received by the GOA
circuit in one clock period is 4. First input terminals INPUT1 of a
GOA1 and a GOA2 are coupled to the first signal terminal. In this
case, N/2+1 is equal to 3, and thus a first input terminal INPUT1
of a GOA3 is coupled to an output terminal OUT of the GOA1. Second
input terminals INPUT2 of a GOA7 and a GOA8 are coupled to the
second signal terminal. In addition, N/2+1 is equal to 3, and thus
a second input terminal INPUT2 of a third last-level GOA (i.e.,
GOA6) is coupled to an output terminal OUT of the last-level GOA
(i.e., GOA8). A touch scan process is performed on a GOA5 and a
GOA6 during the touch scan period. In this case, N/2 cascaded GOA
units, i.e., the GOA5 and the GOA6, are included in the pull-up
node potential holding unit 10, and output terminals of the GOA5
and the GOA6 are not coupled to gate lines, that is, the GOA5 and
the GOA6 do not output gate line scan signals.
[0042] In some embodiments, the number of the clock signals
received by the GOA circuit in one clock period is 6, and the
pull-up node potential holding unit 10 includes three cascaded GOA
units. In some other embodiments, the number of the clock signals
received by the GOA circuit in one clock period is 8, and the
pull-up node potential holding unit 10 includes 4 cascaded GOA
units, and so on.
[0043] In some embodiments, signals from the first signal terminal
and the second signal terminal are not limited. For example, the
signals from the first signal terminal and the second signal
terminal are both start signals. Based on this, the last-level GOA
unit to the (N/2)th last-level GOA unit are reset through the start
signal, and the gate turn-on signals are started to be output from
the first-level GOA unit to the (N/2)th-level GOA units under
control of the start signal.
[0044] In the GOA circuit provided by some embodiments of the
present disclosure, the pull-up node PU of each GOA unit in the
pull-up node potential holding unit 10 is at a high level in the
touch scan period, and in this period, a high level clock signal is
input to each GOA unit in the pull-up node potential holding unit
10, so that the pull-up nodes of the (N/2)-level GOA units located
behind the pull-up node potential holding unit 10 are maintained at
a high level. As a result, the electrical leakage of the pull-up
nodes PU of the several GOA units required to be turned on is
avoided in the touch scan period, thereby avoiding a problem that
the H-line phenomenon occurs at the fixed position in the pixel
area due to the insufficient output voltages from the several GOA
units after the end of the touch scan period.
[0045] In some embodiments, as shown in FIG. 5, each GOA unit
further includes a first input sub-circuit 20, a second input
sub-circuit 30, an output sub-circuit 40, a pull-down control
sub-circuit 50 and a pull-down sub-circuit 60.
[0046] In some embodiments, the first input sub-circuit 20 is
coupled to the first input terminal INPUT1 and the pull-up node PU.
A position on a connection line between the first input sub-circuit
20 and the second input sub-circuit 30 is provided as the pull-up
node PU. The first input sub-circuit 20 is configured to input a
signal from the first input terminal INPUT1 to the pull-up node PU
under control of the first input terminal INPUT1.
[0047] In some embodiments, the second input sub-circuit 30 is
coupled to the second input terminal INPUT2, the pull-up node PU
and the first voltage terminal VSS, and the second input
sub-circuit 30 is configured to output a signal from the first
voltage terminal VSS to the pull-up node PU under control of the
second input terminal INPUT2.
[0048] In some embodiments, the output sub-circuit 40 is coupled to
the pull-up node PU, the clock signal terminal CLK and the output
terminal OUT, and the output sub-circuit 40 is configured to output
a signal from the clock signal terminal CLK to the output terminal
OUT under control of a potential at the pull-up node PU.
[0049] In some embodiments, the pull-down control sub-circuit 50 is
coupled to the second voltage terminal GCH, the pull-up node PU,
the pull-down node PD and the first voltage terminal VSS. A
position on a connection line between the pull-down control
sub-circuit 50 and the pull-down sub-circuit 60 is provided as the
pull-down node PD. The pull-down control sub-circuit 50 is
configured to output a signal from the first voltage terminal VSS
to the pull-down node PD under the control of a potential at the
pull-up node PU, and output a signal from the second voltage
terminal GCH to the pull-down node PD under control of the second
voltage terminal GCH.
[0050] In some embodiments, the pull-down sub-circuit 60 is coupled
to the pull-down node PD, the pull-up node PU, the output terminal
OUT and the first voltage terminal VSS, and the pull-down
sub-circuit 60 is configured to output a signal from the first
voltage terminal VSS to the output terminal OUT and the pull-up
node PU under control of a potential at the pull-down node PD.
[0051] FIG. 6 is a schematic circuit diagram of two GOA units in a
GOA circuit according to some embodiments of the present
disclosure. The structure of each sub-circuit of each GOA unit will
be described below with reference to FIG. 6.
[0052] In some embodiments, as shown in FIG. 6, the first input
sub-circuit 20 includes a first transistor M1. A gate and a first
electrode of the first transistor M1 are coupled to the first input
terminal INPUT1, and a second electrode of the first transistor M1
is coupled to the pull-up node PU.
[0053] In some embodiments, the second input sub-circuit 30
includes a second transistor M2. A gate of the second transistor M2
is coupled to the second input terminal INPUT2, a first electrode
of the second transistor M2 is coupled to the pull-up node PU, and
a second electrode of the second transistor M2 is coupled to the
first voltage terminal VSS.
[0054] In some embodiments, the output sub-circuit 40 includes a
third transistor M3 and a first capacitor C. A gate of the third
transistor M3 is coupled to the pull-up node PU, a first electrode
of the third transistor M3 is coupled to the clock signal terminal
CLK, and a second electrode of the third transistor M3 is coupled
to the output terminal OUT. One end of the first capacitor C is
coupled to the pull-up node PU, and another end of the first
capacitor is coupled to the output terminal OUT.
[0055] In some embodiments, the pull-down control sub-circuit 50
includes a fourth transistor M4, a fifth transistor M5, a sixth
transistor M6 and a seventh transistor M7. A gate and a first
electrode of the fourth transistor M4 are coupled to the second
voltage terminal, and a second electrode of the fourth transistor
M4 is coupled to a gate of the fifth transistor M5 and a first
electrode of the seventh transistor M7. A first electrode of the
fifth transistor M5 is coupled to the second voltage terminal GCH,
and a second electrode of the fifth transistor M5 is coupled to the
pull-down node PD. A gate of the sixth transistor M6 is coupled to
the pull-up node PU, a first electrode of the sixth transistor M6
is coupled to the pull-down node PD, and a second electrode of the
sixth transistor M6 is coupled to the first voltage terminal VSS. A
gate of the seventh transistor M7 is coupled to the pull-up node
PU, and a second electrode of the seventh transistor M7 is coupled
to the first voltage terminal VSS.
[0056] In some embodiments, the pull-down sub-circuit 60 includes
an eighth transistor M8 and a ninth transistor M9. A gate of the
eighth transistor M8 is coupled to the pull-down node PD, a first
electrode of the eighth transistor M8 is coupled to the pull-up
node PU, and a second electrode of the eight transistor M8 is
coupled to the first voltage terminal VSS. A gate of the ninth
transistor M9 is coupled to the pull-down node PD, a first
electrode of the ninth transistor M9 is coupled to the output
terminal OUT, and a second electrode of the ninth transistor M9 is
coupled to the first voltage terminal VSS.
[0057] In some embodiments, any sub-circuit of the above
sub-circuits further includes a plurality of transistors connected
in series with any transistor included in the sub-circuit. In some
embodiments, the transistors described above are all P-type
transistors or N-type transistors. In some examples, the
transistors described above are all P-type transistors, the first
electrodes are sources and the second electrodes are drains. In
some other examples, the transistors described above are all N-type
transistors, the first electrodes are drains and the second
electrodes are sources. The embodiments of the present disclosure
are illustrated by taking an example in which each transistor is an
N-type transistor. In this case, the first voltage terminal VSS is
configured to receive a constant low level, and the second voltage
terminal GCH is configured to receive a constant high level.
[0058] In the GOA circuit shown in FIG. 4, the GOA5 and the GOA6
constitute the pull-up node potential holding unit 10, and the
(N/2)-level GOA units located behind the pull-up node potential
holding unit 10 are a GOA7 and a GOA8. For example, FIG. 6 only
shows a cascading relationship and circuit structures of the GOA5
and the GOA7. The cascading relationship and the circuit structures
of the GOA6 and the GOA8 are the same as the cascading relationship
and the circuit structures of the GOA5 and the GOA7, which will not
be repeated in the embodiments of the present disclosure.
[0059] In some embodiments, a working process of each GOA unit may
be divided into a display period and a touch scan period in an
image frame. The display period includes an input period, an output
period and a reset period. The working process of the GOA circuit
shown in FIG. 6 according to some embodiments will be described
below with reference to FIG. 7.
[0060] In the input period, INPUT1=1, INPUT2=0, CLK=0, PD=0, OUT=0,
and PU=1 in which "1" indicates a high level and "0" indicates a
low level.
[0061] In some embodiments, as shown in FIGS. 6 and 7, the first
transistor M1 is turned on under the control of the first input
terminal INPUT1, the high level of the first input terminal INPUT1
is output to the pull-up node PU via the first transistor M1, and
the high level is stored in the first capacitor C. The sixth
transistor M6 and the seventh transistor M7 are turned on under the
control of the potential at the pull-up node PU, and a potential at
the gate of the fifth transistor M5 is pulled down to the potential
at the first voltage terminal VSS via the seventh transistor M7.
The fourth transistor M4 is turned on under the control of the
second voltage terminal GCH, and the high level of the second
voltage terminal GCH is output to the gate of the fifth transistor
M5 via the fourth transistor M4. A width to length ratio of the
fourth transistor M4 and a width to length ratio of the seventh
transistor M7 are set, so that the gate of the fifth transistor M5
is at a low level, that is, the fifth transistor M5 is in an off
state. Moreover, the potential at the pull-down node PD is pulled
down to a low level of the first voltage terminal VSS via the sixth
transistor M6, and the eighth transistor M8 and the ninth
transistor M9 are in an off state under the control of the
potential at the pull-down node PD. The second transistor M2 is in
an off state under the control of the second input terminal
INPUT2.
[0062] The third transistor M3 is turned on under the control of
the potential at the pull-up node PU, and a low level of the clock
signal terminal CLK is output to the output terminal OUT via the
third transistor M3.
[0063] In the output period, the signal from the clock signal
terminal CLK is output as a gate line scan signal by the output
sub-circuit 40 to the output terminal OUT under the control of the
potential at the pull-up node PU. INPUT1=0, INPUT2=0, CLK=1, PD=0,
OUT=1, PU=1, and PD=0.
[0064] In some embodiments, since the first input terminal INPUT1
receives a low level, the first transistor M1 is in an off state,
and the pull-up node PU is maintained at a high level under an
action of the first capacitor C, so that the third transistor M3 is
maintained in an on state. In this case, a high level of the clock
signal terminal CLK is output as a gate line scan signal to the
output terminal OUT via the third transistor M3 to scan a gate line
to which the output terminal OUT is coupled. Moreover, under a
bootstrap action of the first capacitor C, the potential at the
pull-up node PU is further increased.
[0065] In addition, the states of the second transistor M2, the
fourth transistor M4, the fifth transistor M5, the sixth transistor
M6, the seventh transistor M7, the eighth transistor M8 and the
ninth transistor M9 are the same as the states in the input period,
which are not repeated here.
[0066] In the reset period, the potential at the pull-up node PU is
pulled down by the second input sub-circuit 30 to the potential at
the first voltage terminal VSS under the control of the second
input terminal INPUT2, and the voltage from the second voltage
terminal GCH is output by the pull-down control sub-circuit 50 to
the pull-down node PD under the control of the second voltage
terminal GCH. Under the control of the potential at the pull-down
node PD, potentials at the output terminal OUT and the pull-up node
PU are pulled down by the pull-down sub-circuit 60 to the potential
at the first voltage terminal VSS. INPUT1=0, INPUT2=1, CLK=0,
OUT=0, PU=0, and PD=1.
[0067] In some embodiments, the first transistor M1 is in an off
state under the control of the first input terminal INPUT1. The
second transistor M2 is turned on under the control of the second
input terminal INPUT2, thereby the potential at the pull-up node PU
is pull down to the potential at the first voltage terminal VSS via
the second transistor M2. Under the control of the potential at the
pull-up node PU, the third transistor M3, the sixth transistor M6,
and the seventh transistor M7 are in an off state.
[0068] The fourth transistor M4 is turned on under the control of
the second voltage terminal GCH, and the high level of the second
voltage terminal GCH is output to the gate of the fifth transistor
M5 via the fourth transistor M4. The fifth transistor M5 is turned
on, and the high level of the second voltage terminal GCH is output
to the pull-down node PD via the fifth transistor M5. The eighth
transistor M8 and the ninth transistor M9 are turned on under the
control of the potential at the pull-down node PD, the potential at
the pull-up node PU is pulled down to the potential at the first
voltage terminal VSS via the eighth transistor M8, and the
potential at the output terminal OUT is pulled down to the
potential at the first voltage terminal VSS via the ninth
transistor M9.
[0069] In some embodiments, before a next image frame, the
pull-down control sub-circuit 50 and the pull-down sub-circuit 60
are maintained in the reset state, so that the potential at the
pull-down node PD is maintained at a high level, and the potentials
at the output terminal OUT and the pull-up node PU are maintained
at a low level under the control of the potential at the pull-down
node PD.
[0070] The above is the working process of each GOA unit in the GOA
circuit provided by some embodiments of the present disclosure in
the display period. The working process of the GOA unit shown in
FIG. 6 in the touch scan period in the embodiments of the present
disclosure will be described below with reference to FIG. 7.
[0071] In some embodiments, in the touch scan period, low level
clock signals are input to the (N/2)-level GOA units located behind
the pull-up node potential holding unit 10, so that the gate line
scan signals are not output from the (N/2)-level GOA units located
behind the pull-up node potential holding unit 10 in the touch scan
period.
[0072] High level clock signals are input to each GOA unit in the
pull-up node potential holding unit 10, so that the high level
clock signal is output from the output terminal of each GOA unit in
the pull-up node potential holding unit 10, thereby causing that
the pull-up nodes PU of the (N/2)-level GOA units located behind
the pull-up node potential holding unit 10 are maintained at a high
level in the touch scan period.
[0073] In some embodiments, taking FIG. 4 as an example, and with
reference to FIG. 7, the low level clock signals are input to the
GOA7 and the GOA8 in the touch scan period, so that the gate line
scan signals are not output from the GOA7 and the GOA8 in the touch
scan period. The high level clock signals are input to the GOA5 and
the GOA6, so that the pull-up nodes PU of the GOA7 and the GOA8 are
maintained at a high level in the touch scan period.
[0074] In some embodiments, as shown in FIGS. 4, 6 and 7, in the
touch scan period, the pull-up nodes PU of the GOA5 and the GOA6
are at a high level. Since the clock signals of the GOA5 and the
GOA6 are at a high level, an output signal OUT_5 of the GOA5 and an
output signal OUT_6 of the GOA6 are at a high level. The output
signal OUT_5 is input as a first input signal to the first input
terminal INPUT1 of the GOA7, and the output signal OUT_6 is input
as a first input signal to the first input terminal INPUT1 of the
GOA8. In this case, the first transistors M1 in the GOA7 and the
GOA8 are turned on, which causes that a high level of the output
signal OUT_5 is input via the first transistor M1 in the GOA7 to a
pull-up node PU_7 under control of the output signal OUT_5, and
that a high level of the output signal OUT_6 is input via the first
transistor M1 in the GOA8 to a pull-up node PU_8 under control of
the output signal OUT_6, thereby ensuring that the pull-up node
PU_7 and the pull-up node PU_8 may be maintained at a high level in
the touch scan period, and avoiding the problem that the H-line
phenomenon occurs at the fixed positions due to the insufficient
output voltages from the GOA7 and the GOA8 after the end of the
touch scan period.
[0075] In some embodiments, since the output terminals of the GOA5
and the GOA6 are not coupled to the gate lines, a display effect of
a display panel will not be affected by the output signals of the
GOA5 and the GOA6 in the touch scan period.
[0076] In some embodiments, since the pull-up nodes PU of the
(N/2)-level GOA units located behind the pull-up node potential
holding unit 10 are at a high level, for example, the pull-up node
PU_7 of the GOA7 and the pull-up node PU_8 of the GOA8 are at a
high level in the touch scan period, which causes that the third
transistors M3 in the GOA7 and the GOA8 are turned on, and the low
level of the clock signal terminal CLK is output to the output
terminal OUT via the third transistor M3 in each of GOA7 and the
GOA8.
[0077] In some embodiments, as shown in FIGS. 4-6, each of the
(N/2)-level GOA units located behind the pull-up node potential
holding unit 10 further includes a denoising sub-circuit 70. In the
(N/2)-level GOA units located behind the pull-up node potential
holding unit 10, the denoising sub-circuit 70 of any GOA unit is
coupled to the first voltage terminal VSS, the output terminal OUT
of the same-level GOA unit and the output terminal OUT of a
corresponding-level GOA unit in the pull-up node potential holding
unit 10. The denoising sub-circuit 70 is configured to denoise the
output signal of the output terminal OUT of the same-level GOA unit
under control of the output signal of the output terminal OUT of
the corresponding-level GOA unit in the pull-up node potential
holding unit 10 in the touch scan period.
[0078] In some embodiments, with reference to FIG. 6, the denoising
sub-circuit 70 includes a tenth transistor M10. A gate of the tenth
transistor M10 is coupled to the output terminal OUT of the
corresponding-level GOA unit in the pull-up node potential holding
unit 10, a first electrode of the ten-transistor M10 is coupled to
the output terminal OUT of the same-level GOA unit, and a second
electrode of the tenth transistor M10 is coupled to the first
voltage terminal VSS.
[0079] In some embodiments, in the touch scan period, the tenth
transistors M10 in the GOA7 and the GOA8 are turned on under the
control of the output signal OUT_5 of the GOA5 and the output
signal OUT_6 of the GOA6, and potentials at the output terminals
OUT of the GOA7 and the GOA8 are pulled down to the potential at
the first voltage terminal VSS via the tenth transistors M10, so as
to denoise signals output from the output terminals OUT of the GOA7
and the GOA8.
[0080] In some embodiments, the GOA units in the pull-up node
potential holding unit 10 denoise the output signals from the
(N/2)-level GOA units located behind the pull-up node potential
holding unit 10, thereby eliminating the GCL signal and the wire
associated with the GCL signal. Compared to the fact that a
transistor controlled by the GCL signal is added to each GOA unit
of the GOA circuit, only the (N/2)-level GOA units located behind
the pull-up node potential holding unit 10 of the GOA circuit
provided by the embodiments of the present disclosure include the
tenth transistors M10 configured for denoising, which reduces the
number of transistors in the GOA circuit and is advantageous for
saving the power consumption, thereby facilitating a development of
a narrow frame of the display panel and a development of a low
power consumption.
[0081] Some embodiments of the present disclosure provides a method
of driving the GOA circuit provided by the foregoing embodiments,
and the method includes: providing the low level clock signals to
the (N/2)-level GOA units located behind the pull-up node potential
holding unit 10 in the touch scan period, so that the gate line
scan signals are not output from the (N/2)-level GOA units located
behind the pull-up node potential holding unit 10 in the touch scan
period; and providing the high level clock signals to each GOA unit
in the pull-up node potential holding unit 10, so that the high
level signal is output from the output terminal of each GOA unit in
the pull-up node potential holding unit 10, thereby causing that
the pull-up nodes PU of the (N/2)-level GOA units located behind
the pull-up node potential holding unit 10 are maintained at a high
level in the touch scan period.
[0082] The specific working process of the GOA circuit in the touch
scan period has been described in detail in some embodiments of the
present disclosure, which is not repeated here.
[0083] In the method of driving the GOA circuit provided by the
foregoing embodiments of the present disclosure, the low level
clock signals are input to the (N/2)-level GOA units located behind
the pull-up node potential holding unit 10 in the touch scan
period, so that the gate line scan signals are not output from the
(N/2)-level GOA units located behind the pull-up node potential
holding unit 10 in the touch scan period. Moreover, the high level
clock signals are input to each GOA unit in the pull-up node
potential holding unit 10, so that the high level signal is output
from the output terminal of each GOA unit in the pull-up node
potential holding unit 10, thereby causing that the pull-up nodes
PU of the (N/2)-level GOA units located behind the pull-up node
potential holding unit 10 are maintained at a high level in the
touch scan period. Thereby, the electrical leakage of the pull-up
nodes PU of the several GOA units required to be turned on is
avoided in the touch scan period, thereby avoiding the problem that
the H-line phenomenon occurs at the fixed positions in the pixel
area due to the insufficient output voltages from the several GOA
units after the end of the touch scan period.
[0084] In some embodiments, the (N/2)-level GOA units located
behind the pull-up node potential holding unit include denoising
sub-circuits, and in the touch scanning period, the high level
signals output from the output terminals of GOA units in the
pull-up node potential holding unit may also denoise the output
signals from the (N/2)-level GOA units located behind the pull-up
node potential holding unit, thereby avoiding that the gate line
scan signals are output in the touch scan period, and avoiding
affecting the display effect of the display panel.
[0085] The driving method provided by the embodiments of the
present disclosure may further include a driving method in the
display period, and the display period includes an input period, an
output period and a reset period.
[0086] In the input period, the signal from the first input
terminal INPUT1 is input by the first input sub-circuit 20 to the
pull-up node PU under the control of the first input terminal
INPUT1.
[0087] In the output period, the signal from the clock signal
terminal CLK is output as a gate line scan signal by the output
sub-circuit 40 to the output terminal OUT under the control of the
potential at the pull-up node PU.
[0088] In the reset period, the potential at the pull-up node PU is
pulled down by the second input sub-circuit 30 to the potential at
the first voltage terminal VSS under the control of the second
input terminal INPUT2, and the voltage from the second voltage
terminal GCH is output by the pull-down control sub-circuit 50 to
the pull-down node PD under the control of the second voltage
terminal GCH. Under the control of the potential at the pull-down
node PD, the potentials at the output terminal OUT and the pull-up
node PU are pulled down by the pull-down sub-circuit 60 to the
potential at the first voltage terminal VSS.
[0089] In some embodiments, the working processes of the input
period, the output period and the reset period have been described
in detail above, which are not repeated here.
[0090] As shown in FIG. 8, some embodiments of the present
disclosure provide a touch display apparatus, and the display
apparatus includes the GOA circuit described in the above
embodiments. Beneficial effects of the display apparatus provided
by the embodiments of the present disclosure are the same as the
beneficial effects of the GOA circuit provided by the foregoing
embodiments, which are not repeated here.
[0091] In some embodiments, the touch display apparatus includes at
least a liquid crystal display apparatus or an organic
light-emitting diode display apparatus. For example, the touch
display apparatus may be any product or component having a display
function such as a liquid crystal display, a liquid crystal
television, a digital photo frame, a mobile phone or a tablet
computer. The embodiments of the present disclosure do not limit a
touch type of the touch display apparatus. For example, the touch
display apparatus may be a display apparatus using an in cell touch
technology.
[0092] The foregoing descriptions are merely some implementation
manners of the present disclosure, but the protection scope of the
present disclosure is not limited thereto. Any person skilled in
the art could readily conceive of changes or replacements within
the technical scope of the present disclosure, which shall all be
included in the protection scope of the present disclosure.
Therefore, the protection scope of the present disclosure shall be
subject to the protection scope of the claims.
* * * * *